thanks for your help and reports!
Build #175 should be discarded, it was a bogus build, and it used the wrong kernel. So 176 is the first build based on the 4.14 based release branch (and 173 is the last with 4.11 kernel).
For 176, once you’ve booted, can you please inspect /var/log/Xorg.0.log? what do you see there?
Then can you run (on the root serial console)
systemctl stop sddm
and share its output?
Then, can you start Xserver with:
And then report the output of:
What I suspect (which I can see on one of my monitor) is that some video modes don’t work.
For example, in my case switching from 4K to 1080p bring the display back up:
xrandr --output HDMI-1 --mode 1920x1080
I am not seeing any USB issues though…